Lock for filler caps



. H. R. MURCHISON LOOK FOR FILLER CAPS Filed August 12, 1925 Qwvwntoa:

Patented Apr. 20,1926.

UNITED STATES PATENT OFFICE.

LOCK FOR FILLER cars.

Application filed August 12, 1925. Serial No. 49,808.

To all whom it may concern.

- Be it known that I, HUGH R. MURcHIsoN, a citizen of the United States, residing at Columbia, in the county of- Richland and State of South Carolina, have invented new and useful Improvements in Locks for Filler Caps, of which the following is a specification.

This invention relates to looks for filler caps, and more particularly to locks for caps which are used to close the filling tubes of automobile radiators, gasolene tanks, and

the like. 1

Various devices have been constructed for the purpose of preventing an unauthorized person from tampering with or removing the caps fromradiators and gasolene tanks on automobiles, but they have not been found practical or commercially feasible due to the fact that they either necessitate the reorganization and design of the cap ,or nlpple or both, or they are of such a character and design which makes them rather expenslve in themselves and expensive to install. Accordingly one of the objects of this m1 vention resides in the production of a locking device of a character which is very simple, durable, and comprises very few parts.

Another object of this invention resides 1n the production of a locking device for filler caps which does not necessitate any change or reorganization in the design or make of the filling nipple.

The locking device constructed in accordance with my invention comprises a circular cap having a cylindrical boss extending inwardly from the exterior surface of the cap, a cylindrical lock casing comprising a rotary barrel and a lever mounted within said-boss, and a cam surrounding said boss carrying a retaining means for example, a pair of pegs for the reception of the end of the lever therebetween, the movement of the lever causing a consequent movement of the cam into and out of contact with the inner periphery or face of the filler tube or nipple.

For the purposes of description, an embodiment of my invention is illustrated in the accompanying drawings, in which- Fi re 1 is a plan view of a filler ca-p provlded with my invention.

Figure 2 is a sectional view taken on the line 2-2 of Fig.1.

Figure 3 is a sectional view taken on the plane of line 3-3 of Fig. 2, having parts of the lock casing broken away.

Figure 4 is a detail view of the cam.

Referring to the drawings, reference numeral 1 represents the filling neck of a fuel tank for the delivery of fuel therethrough. The filling neck is provided with an external screw thread 2 adapted to receive the internally threaded cap 3. The cap 3 engages the external screw threads on the filling neck 1 in the ordinary manner. the cap 3 serve as an efficient seal for the tank I prefer to employ a washer or packmg ring 4 as shown in Fig. 2. i

The filler cap 3 is provided with an eccentric-ally disposed opening 5 for the reception of a cylindrical lock casing 6. The interior of the cap 3is extended inwardly to form a cylindrical boss 8 within which is disposed the lock casinfg 6. Mounted about the circumference o the cylindrical boss 8 is a cam 9 carrying attached to the end of the cylindrical boss 8 means of fastening means 18 as screws or rivets as shown in Figs. 2 and 3. The lock caslng 17 is provided. with a slot 12, the purpose of wh1ch Wlll be apparent from the description hereinafter set forth.

Mounted within the lock casing 6 is a rotary barrel 14 which is provided with a keyhole for the reception of a key 15. Disposed about the lower end of the rotary barrel 14 1s a lever 11, one end of engagement with a spring 13 carried by the base plate forming a part of the lock, and is operated by the'key 15.

The lever 11 is in-constant engagement wlth the pegs 10 of the earn 9, and as the lever 11 1s moved either to the right or to the left by the key 15, so is the cam 9 correspondingly moved. The limit of movement of the cam is determined by the size of the slot or the portion of the lock casing 17 which is cut awa to form such slot. The size of the slot which limits the movement of the cam with respect to the inner peripher or surface of the filling neck is clearly s own in Fig. 3. It is to be noted pair of pegs 10 which is retained 1n position by the lock casing 17 2 a5 1 In order to have which is in i that the size of this slot is not constant but must be varied to accommodate, the differenttypes of filling necks,

. The device operates as follows a After the cap has been secured or screwed on the filli neck, the key is manipulated to move the ever 11 and cam 9 with which it is in constant engagement to the dotted line position shown in-Fig. 3 in which the enlarged portion of the cam is pressed against the inner periphery or surface 16 of 4 the filling neck 1. Now any attempted rotation of the cap to the left to remove ity from the filling neck will tend to cause the enlarged portion of the cam to wedge itself more forcibly against the surface 16; and

' When it is desired to remove the cap, thethus make it imposible to unscrew the cap;

key is inserted and operated to retract the cam 9 through the medium of the lever'll,

whereupon t e cam is returned to its full line position shown in Fig. 3, in which the cam 9 is free from the inner surface 16 of the filling neck 1, and offers no resistance to the rotation of the cap.

From the foregoing description itwill be apparent that a lockm device made in ac-- 'cordance with the teac ings of this inven tion comprises avery simple anddurable structure which can be manufactured commercially at a compartively low cost, and which is adapted for an fillin necks whether of the screw. or ot er wel known pes. Obviously, the invention isnot limited to the specific embodiments thereof herein illustrated and described, but is capable of variations andother applications withmany y in t e spirit and scope of the invention as set out in the appended claims.

Having thus described my invention, what v I claim as new and desire to secure by Leti ters Patent is:

FLA. lock for filler caps comprising a locking cam mounted within the cap and and bind against the in-' adapted to en'ga ner surface of t e filler. nipple, and a key operated lever within said cap in constant engagement with said cam to move the cam into and out of contact with the inner face of the filler nipple.

2. A look for filler caps comprising a locking cam mounted within the'cap and adapted to engage and bind against the inner Surface of the filler nipple, and a lock casing mounted within said cap and operable fromithe outside by a key and comprising a lever in operative engagement with said cam to move said cam into and out of operative relation with the filler nipple.

3. A look for filler caps comprising a looking cam mountedv within the cap and carrying a pair of pegs on its under side, and a' for filler caps comprisingthe posed lever carried by said barrel and having I a cam in operative engagement with the lever adapted to cramp against the'inner face of the filler nipple, whereby when said lever is moved said cam will be forced into locking engagement with said. face and the turning of the cap in a direction to remove the same will be prevented. p

- HUGH R. MURCHISON. 

